been trying the OS 6 and a few of OS 5 (*.979, *.1014, *.442, *.593, *.743) but still all have the same result.
My battery turned extremely hot when using the 3G network and it was also drained so fast like a broken battery (i hv never had this problem when using only GPRS/EDGE network).

Ok, just to confirm, right now and not based on your memory, if you switch mobile network options to 2G only, charge the battery, and test for a few hours, the battery does not drain rapidly and BlackBerry does not get overly warm?Posted via BlackBerryForums.com Mobile

Ok, just to confirm, right now and not based on your memory, if you switch mobile network options to 2G only, charge the battery, and test for a few hours, the battery does not drain rapidly and BlackBerry does not get overly warm?Posted via BlackBerryForums.com Mobile

Yes, if i use only the 2G network, everything's fine. no hot or drained battery.

The only thing I can think of that is not necessairly something wrong is that the battery is draining rapidly and the battery is getting warm because the BlackBerry is hitting the network frequently. Maybe it is apps you have running, or something about your usage patterns, or location in a 3G fringe.

The fact that there is not issue on 2G indicates to me there probably is no problem with the device hardware or battery. I also doubt you will solve the problem by finding an ideal OS version.Posted via BlackBerryForums.com Mobile

The only thing I can think of that is not necessairly something wrong is that the battery is draining rapidly and the battery is getting warm because the BlackBerry is hitting the network frequently. Maybe it is apps you have running, or something about your usage patterns, or location in a 3G fringe.

The fact that there is not issue on 2G indicates to me there probably is no problem with the device hardware or battery. I also doubt you will solve the problem by finding an ideal OS version.Posted via BlackBerryForums.com Mobile

App on my blackberry, they're all just the standard apps like Yahoo msgr,windows live msgr and blackberry msgr itself. blackberry is made to make all of them stay connected right?

3G network is mostly found full. i don't think this blackberry works har
der than any other phone using the 3G network. It's just a standard signal search that i guess it shouldn't give any issue to the phone.

IM apps are notorious causes of shortened battery life. I don't know why you would see a pronounced difference on 3G, but maybe it's normal. So, to find out, shut down, completely shut down, Yahoo and Live messenger. Make sure they are not running in the background. Test for 24 hours on 3G and see what happens.Posted via BlackBerryForums.com Mobile

IM apps are notorious causes of shortened battery life. I don't know why you would see a pronounced difference on 3G, but maybe it's normal. So, to find out, shut down, completely shut down, Yahoo and Live messenger. Make sure they are not running in the background. Test for 24 hours on 3G and see what happens.Posted via BlackBerryForums.com Mobile

i've done all possible test i could do to see the cause of this battery shortage and drainage. Including turning off all apps.

The battery got worst especially when i try to download anything using the 3G network.

I've met someone who had similiar case like me and after he found the best suited OS5 for his phone (which is *.743 i'm using right now), then no
battery shortage or drainage. but this *.743 is not really good on my phone.